In recent years, carbon materials having a graphene sheet structure have attracted attention because they have high modulus of elasticity and high conductivity. Such carbon materials having a graphene structure can be combined with synthetic resins to thereby reinforce products from the synthetic resins or impart conductivity thereto. In particular, graphene sheets, carbon nanotubes, thin graphite films, and the like are nano-size, and they have large specific surface areas. Therefore, when the carbon materials are combined with resins, it is believed that the above effects can be exerted more apparently.
Generally, in order to sufficiently exert such effects as a composite material, it is preferred that the carbon material be uniformly dispersed in a matrix resin. Thus, a process of providing uniform dispersion using a common solvent for the carbon material and the resin is disclosed in the following Patent Literature 1. According to this process, it is possible to obtain a resin composite material in a uniform dispersion state as long as a common solvent for the resin and the carbon material is present.